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1.
Braz. j. biol ; 83: e244127, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278526

Resumo

Abstract Tiliroside is a glycosidic flavonoid present in many plants species including Helicteres velutina K. Schum (Malvaceae sensu lato), commonly known in Brazil as "pitó". This molecule has been shown to have many biological activities, however no study has been carried out to investigate the toxicity of this substance. The present work aimed to evaluate the possible cellular toxicity in silico, in vitro and ex-vivo of the kaempferol-3-O-β-D-(6"-E-p-coumaroyl) glucopyranoside (tiliroside), through chemical structure analysis, toxicity assessment and predictive bioactive properties, using human samples for in vitro and ex-vivo tests. The in silico analysis suggests that tiliroside exhibited great absorption index when penetrating biological membranes. In addition, it also displayed considerable potential for cellular protection against free radicals, and anticarcinogenic, antioxidant, antineoplastic, anti-inflammatory, anti-hemorrhagic and antithrombotic activities. The assessment of the hemolytic and genotoxic effects of tiliroside showed low hemolysis rates in red blood cells and absence of cellular toxicity in the oral mucosa cells. The data obtained indicate that this molecule could be a promising therapeutic approach as a possible new drug with biotechnological potential.


Resumo O tilirosídeo é um flavonóide glicosídico presente em muitas espécies de plantas, incluindo Helicteres velutina K. Schum (Malvaceae sensu lato), conhecida no Brasil como "pitó". Esta molécula mostrou ter muitas atividades biológicas, porém nenhum estudo foi realizado para investigar a toxicidade dessa substância. O presente trabalho teve como objetivo avaliar a possível toxicidade celular in silico, in vitro e ex-vivo do kaempferol-3-O-β-D- (6 "-Ep-coumaroil) glucopiranosídeo (tilirosídeo), por meio de análises de estrutura química, toxicidade avaliação e propriedades bioativas preditivas, utilizando amostras humanas para testes in vitro e ex-vivo. A análise in silico sugere que o tilirosídeo exibe bom índice de absorção para penetrar nas membranas biológicas. Além disso, apresentou considerável potencial de proteção celular contra os radicais livres e com atividades anticarcinogênica, antioxidante, antineoplásica, antiinflamatória, anti-hemorrágica e antitrombótica. A avaliação dos efeitos hemolíticos e genotóxicos do tilirosídeo mostrou baixas taxas de hemólise nas hemácias e ausência de toxicidade em células da mucosa oral. Os dados obtidos indicam que esta molécula pode possuir uma abordagem terapêutica promissora como uma possível nova droga com potencial biotecnológico.


Assuntos
Humanos , Extratos Vegetais , Quempferóis/toxicidade , Flavonoides , Simulação por Computador , Brasil
2.
Acta sci. vet. (Impr.) ; 51: Pub. 1910, 2023. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1435028

Resumo

Background: The feline immunodeficiency virus (FIV) is responsible for a retroviral disease that affects domestic and wild cats worldwide, causing Feline Acquired Immunodeficiency Syndrome (FAIDS). FIV is a lentivirus from the family Retroviridae and its genome has 3 main structural genes: gag, pol and env. Phylogenetic studies have classified FIV into 7 subtypes according to the diversity among strains from the World, mainly in the env gene. Epidemiological analyses have demonstrated the high predominance of FIV-A and FIV-B. This in silico study aimed to perform a phylogenetic analysis to study FIV diversity worldwide. Materials, Methods & Results: A total of 60 whole genome sequences (WGS) and 122 FIV env gene sequences were included in 2 datasets, which were aligned using MAFFT version 7. Recombination among genomes and/or env genes was analyzed with RDP5 software. Phylogenetic analyses with both datasets were performed, after removing the recombinant sequences, by the W-IQ-TREE and constructed and edited by the FigTree. A total of 12 recombination events involving 19 WGS were detected. In addition, 27 recombination events involving 49 sequences were observed in the env gene. A high rate of recombinants was observed inter-subtypes (A/B and B/D) and intra-subtypes (A/A). All recombinants were removed from the subsequent phylogenetic analyses. Phylogenies demonstrated 6 distinct main clades, 5 from domestic cats (A, B, C, E, U) and 1 from wild cat sequences (W) in the WGS, as well as in the specific env gene analyses. Most clustered with subtype B sequences. In the WGS analysis, clade B had a prevalence of 65.9% Brazilian sequences (27/41) and 2.4% Japanese sequences (1/41). In the env gene analyses, clade B showed a prevalence of 43.8% of Brazilian sequences (32/73) and 20.5% of USA sequences (15/73). The results of both analyses also confirm the FIV-wide geographical distribution around the world. In the phylogenetic analyses carried out with WGS, sequences from China (1/41; 2.4%), Colombia (1/41; 2.4%) and the USA (1/41; 2.4%) were identified in clade A; sequence from Canada in clade C (1/41; 2.4%); sequence from Botswana belonged to clade E (1/41; 2.4%); sequences from Brazil clustered into clade U (2/41; 5% - data not yet published); and sequences belonging to the clade W were from Canada (1/41; 2.4%) and the USA (5/41; 12.3%). Specific env gene phylogenetic analyses showed sequences from Colombia (1/73; 1.4%), France (2/73; 2.7%), the Netherlands (3/73; 4.1%), Switzerland (2/73; 2.7%), USA (6/73; 8.3%), belonging to clade A; sequence from Canada belonging to clade C (1/73; 1.4%); sequences from Brazil belonging to clade U (2/73; 5% - data not yet published); and sequences belonging to clade W from the USA (6/73; 8.3%). Discussion: The results presented here demonstrate that FIV has a rapid viral evolution due to recombination and mutation events, more specifically in the env gene, which is highly variable. Currently, this retrovirus is classified into 7 subtypes (A, B, C, D, E, F and U-NZenv) according to their high genomic diversity. It also highlighted the importance of in silico sequence and phylogeny studies to demonstrate evolutionary processes. This was the first study to address the WGS FIV diversity with a phylogenetic approach.


Assuntos
Filogenia , Recombinação Genética , Retroviridae/genética , Vírus da Imunodeficiência Felina/genética , Simulação por Computador
3.
Braz. j. biol ; 83: e247237, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339386

Resumo

Abstract Novel coronavirus (nCoV) namely "SARS-CoV-2" is being found responsible for current PANDEMIC commenced from Wuhan (China) since December 2019 and has been described with epidemiological linkage to China in about 221 countries and territories until now. In this study we have characterized the genetic lineage of SARS-CoV-2 and report the recombination within the genus and subgenus of coronaviruses. Phylogenetic relationship of thirty nine coronaviruses belonging to its four genera and five subgenera was analyzed by using the Neighbor-joining method using MEGA 6.0. Phylogenetic trees of full length genome, various proteins (spike, envelope, membrane and nucleocapsid) nucleotide sequences were constructed separately. Putative recombination was probed via RDP4. Our analysis describes that the "SARS-CoV-2" although shows great similarity to Bat-SARS-CoVs sequences through whole genome (giving sequence similarity 89%), exhibits conflicting grouping with the Bat-SARS-like coronavirus sequences (MG772933 and MG772934). Furthermore, seven recombination events were observed in SARS-CoV-2 (NC_045512) by RDP4. But not a single recombination event fulfills the high level of certainty. Recombination mostly housed in spike protein genes than rest of the genome indicating breakpoint cluster arises beyond the 95% and 99% breakpoint density intervals. Genetic similarity levels observed among "SARS-CoV-2" and Bat-SARS-CoVs advocated that the latter did not exhibit the specific variant that cause outbreak in humans, proposing a suggestion that "SARS-CoV-2" has originated possibly from bats. These genomic features and their probable association with virus characteristics along with virulence in humans require further consideration.


Resumo O novo coronavírus (nCoV), nomeadamente "SARS-CoV-2", foi considerado responsável pela pandemia atual iniciada em Wuhan (China) desde dezembro de 2019 e foi descrito com ligação epidemiológica à China em cerca de 221 países e territórios até agora. Neste estudo, caracterizamos a linhagem genética do SARS-CoV-2 e relatamos a recombinação dentro do gênero e subgênero dos coronavírus. A relação filogenética de 39 coronavírus pertencentes a seus quatro gêneros e cinco subgêneros foi analisada usando o método de Neighbour-joining usando MEGA 6.0. Árvores filogenéticas do genoma de comprimento total, várias proteínas (espícula, envelope, membrana e nucleocapsídeo), sequências de nucleotídeos foram construídas separadamente. A recombinação putativa foi testada via RDP4. Nossa análise descreve que o "SARS-CoV-2", embora mostre grande semelhança com as sequências de Bat-SARS-CoVs em todo o genoma (dando semelhança de sequência de 89%), exibe agrupamento conflitante com as sequências de coronavírus do tipo Bat-SARS (MG772933 e MG772934) Além disso, sete eventos de recombinação foram observados em SARS-CoV-2 (NC045512) por RDP4. Mas nem um único evento de recombinação preenche o alto nível de certeza. A recombinação está alojada mais em genes de proteína de pico, principalmente, do que no resto do genoma, indicando que o cluster de ponto de interrupção surge além dos intervalos de densidade de ponto de interrupção de 95% e 99%. Os níveis de similaridade genética observados entre "SARS-CoV-2" e Bat-SARS-CoVs defendem que o último não exibe a variante específica que causa surto em humanos, sugerindo que "SARS-CoV-2" tenha se originado possivelmente de morcegos. Essas características genômicas e sua provável associação com as características do vírus, juntamente com a virulência em humanos, requerem uma consideração mais aprofundada.


Assuntos
Humanos , Animais , Quirópteros , COVID-19 , Filogenia , Simulação por Computador , Genoma Viral/genética , SARS-CoV-2
4.
Semina ciênc. agrar ; 43(5): 1941-1956, jun. 2022. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1395492

Resumo

Whole and halved strawberries were dried by using three methods, which were solar tunnel drying, shade drying, and microwave drying (180W, 540W, and 900W) to determine drying characteristic and modelling. The researchers measured solar irradiation at ambient and drying air temperatures and air velocity at specific intervals in various parts of the dryer. How microwave drying (180, 540, and 900 W) affected the drying time and drying ratio of the whole and halved strawberry samples was investigated. In addition, the data on the drying process were applied to 5 different mathematical models, which were Weibull distribution, Midilli et al., Jena and Das and Aghbashlo et al. Equation Models. The researchers compared the performance levels of the models according to correlation coefficient (R2), chi-square value (χ2), besides the root mean square error (RMSE) between moisture ratios that were observed and predicted. Furthermore, the Weibull Distribution and Midilli et al. models were found to reveal the ratio of drying in a satisfactory way for all the methods of drying.(AU)


Morangos inteiros e cortados ao meio foram secos usando três métodos, que foram secagem em túnel solar, secagem à sombra e secagem por micro-ondas (180W, 540W e 900W) para determinar a característica de secagem e modelagem. Os pesquisadores mediram a irradiação solar nas temperaturas ambiente e de secagem do ar e a velocidade do ar em intervalos específicos em várias partes do secador. Como a secagem por micro-ondas (180, 540 e 900 W) afetou o tempo de secagem e a proporção de secagem das amostras inteiras e cortadas de morango foi investigado. Além disso, os dados do processo de secagem foram aplicados a 5 modelos matemáticos diferentes, que foram a distribuição de Weibull, Midilli et al., Jena e Das e Aghbashlo et al. Modelos de equação. Os pesquisadores compararam os níveis de desempenho dos modelos de acordo com o coeficiente de correlação (R2), valor do qui-quadrado (χ2), além da raiz do erro quadrático médio (RMSE) entre as razões de umidade observadas e previstas. Além disso, a Distribuição Weibull e Midilli et al. os modelos revelaram a proporção de secagem de forma satisfatória para todos os métodos de secagem.(AU)


Assuntos
Fragaria/fisiologia , Conservação de Alimentos/instrumentação , Análise de Dados
5.
Rev. bras. zootec ; 51: e20210131, 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1442763

Resumo

This study aimed to introduce R package pedSimulate, which was built to simulate pedigree, genetic merit, phenotype, and genotype data. These are amongst the most important data types that animal breeders and quantitative geneticists deal with. Twenty pedigrees with ten generations were simulated applying different combinations of three parameters: genetic variance (10 vs. 20), proportion of males selected (10 vs. 20%), and the pattern for selecting females (random, positively, or negatively based on own phenotype or parent average). Males were selected positively based on parent average. Consequently, assortative mating was applied to the pedigrees in which females were positively selected based on their own phenotype or parent average. Disassortative mating was applied to the pedigrees in which females were selected negatively based on phenotype or parent averages. Genetic gain and response to selection over generations were positive for all the pedigrees due to high selection intensity on males, mating each male with multiple females, and moderate to high heritability (0.25 and 0.40 for genetic variances 10 and 20, and the residual variance of 30). Genetic variance showed a slightly increasing trend over generations by assortative mating and lower selection intensity on males. Selection intensity on females was the same in all the pedigrees. This study provided examples of how R package pedSimulate can be adopted for pedigree, genetic merit, phenotype, and genotype data simulation in animal breeding studies. By using different functions and combining different parameters for their arguments, many scenarios can be simulated by R package pedSimulate.(AU)


Assuntos
Animais , Masculino , Feminino , Simulação por Computador , Cães/genética , Variação Genética
6.
Ciênc. rural (Online) ; 52(8): e20201128, 2022. ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1364729

Resumo

Forecast the price of agricultural goods is a beneficial action for farmers, marketing agents, consumers, and policymakers. Today, managing this product security requires price forecasting models that are both efficient and reliable for a country's import and export. In the last few decades, the Autoregressive Integrated Moving Average (ARIMA) model has been widely used in economics time series forecasting. Recently, many of the time series observations presented in economics have been clearly shown to be nonlinear, Machine learning (ML) modelling, conversely, offers a potential price forecasting technique that is more flexible given the limited data available in most countries' economies. In this research, a hybrid price forecasting model has been used, through a novel clustering technique, a new cluster selection algorithm and a multilayer perceptron neural network (MLPNN), which had many advantages and using monthly time series of Thai rice FOB price form November 1987 to October 2017. The empirical results of this study showed that the value of root mean square error (RMSE) equals 14.37 and the Mean absolute percentage error (MAPE) equals 4.09% for the hybrid model. The evaluation results of proposed method and comparison its performance with four benchmark models, by monthly time series of Thailand rice FOB price from November 1987 to October 2017 showed the outperform of proposed method.


Prever o preço dos produtos agrícolas é uma ação benéfica para agricultores, agentes de marketing, consumidores e legisladores. Hoje, o gerenciamento da segurança desse produto requer modelos de previsão de preços eficientes e confiáveis para a importação e exportação de um país. Nas últimas décadas, o modelo Autoregressive Integrated Moving Average (ARIMA) tem sido amplamente utilizado na previsão de séries temporais da economia. Recentemente, muitas das observações de séries temporais apresentadas em economia têm se mostrado claramente não lineares. A modelagem de aprendizado de máquina (ML), por outro lado, oferece uma técnica de previsão de preços potencial que é mais flexível, apresentados os dados limitados disponíveis na maioria dos países. Nesta pesquisa, um modelo híbrido de previsão de preços foi usado, por meio de uma nova técnica de agrupamento, um novo algoritmo de seleção de agrupamento e uma rede neural perceptron multicamadas (MLPNN), que teve muitas vantagens, e usando séries temporais mensais de preços FOB do arroz tailandês de novembro 1987 a outubro de 2017. Os resultados empíricos deste estudo mostraram que o valor da raiz do erro quadrático médio (RMSE) é igual a 14,37 e o erro percentual absoluto médio (MAPE) é igual a 4,09% para o modelo híbrido. Os resultados da avaliação do método proposto e a comparação de seu desempenho com quatro modelos de benchmark, por séries temporais mensais de preço FOB do arroz tailandês de novembro de 1987 a outubro de 2017, mostram o desempenho superior do método proposto.


Assuntos
Oryza , Algoritmos , Análise por Conglomerados , Estudos de Séries Temporais , Redes Neurais de Computação , Aprendizado de Máquina/economia
7.
Rev. Ciênc. Agrovet. (Online) ; 21(4): 370-383, dez. 2022. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1413440

Resumo

The aim of this study was to evaluate the fit of semi-empirical models for growth and productivity in soya cultivars under irrigation and rainfed conditions in the state of Alagoas. Two experiments were conducted, the first during the dry season from 14/11/18 to 03/04/19 (140 days), and the second during the rainy season from 20/06/19 to 28/10/19 (130 days) in the coastal-tableland region of Alagoas. The experimental design was of randomised blocks, with the treatments comprising six cultivars of different maturity groups and growth habits (M 6210, M 6410, BMX-Potência, AS 3730, M 8349 and BRS-9383). The following were evaluated: plant height, dry matter and leaf area index (LAI). The sigmoidal and pic log-normal logistic models showed a significant statistical fit (p<0.05) to the growth variables and adjusted coefficients of determination (R2adj), with a maximum of 0.994 and 0.990, respectively. The observed values and those estimated by the models showed a high association by the Pearson (r) and Willmott (d) indices, with a low Standard Error of the Estimate (SEE). The BRS-9383 cultivar had the highest observed and estimated growth rates. Under irrigation, the maximum values for plant height were 98.45 and 110.35 cm, with maximum dry matter of 65.88 and 78.70 g, and maximum LAI of 7.68 and 7.60. Under rainfed conditions, the maximum plant height was 62.91 and 72.85 cm, maximum dry matter was 40.0 and 44.91 g, and the maximum LAI was 6.34 and 6.26. The highest agricultural yields under irrigation were 6.19 and 5.90 Mg ha-1 for the AS 3730 and M 8349 cultivars. Under rainfed conditions, the M 6410 and M 8349 cultivars stood out with grain yields of 3.60 and 3.30 Mg ha-1. Thus, growth models can be used to help analyse growth as a function of days after planting.(AU)


Objetivou-se com este trabalho avaliar o ajuste de modelos semiempíricos de crescimento e a produtividade de cultivares de soja submetida a condições de irrigação e sequeiro no Estado de Alagoas. Foram conduzidos dois experimentos, o primeiro durante a estação seca de 14/11/2018 a 03/04/19 (140 dias), e o segundo na estação chuvosa de 20/06/19 a 28/10/2019 (130 dias) na região dos Tabuleiros Costeiros de Alagoas. O delineamento experimental foi em blocos casualizados e os tratamentos foram seis cultivares com diferentes grupos de maturação e hábitos de crescimento (M 6210, M 6410, BMX-Potência, AS 3730, M 8349 e BRS-9383). Foram avaliadas a altura das plantas, matéria seca e índice de área foliar (LAI). Os modelos logísticos, sigmoidal e pic log normal PHresentaram ajustes estatísticos significativos (p<0,05) para as variáveis de crescimento e coeficientes de determinação ajustado (R2ajs) máximo de 0,994 e 0,990, respectivamente. Os valores observados e estimados pelos modelos PHresentaram alta associação pelos índices de Pearson (r), Willmott (d) e baixo Erro Padrão de Estimativa (EPE). A cultivar BRS-9383 teve as maiores taxas de crescimento observados e estimados. Em condições de irrigação, os valores de altura de plantas máxima foram 98,45 e 110,35 cm, matéria seca máxima de 65,88 e 78,70 g e o LAI máximo de 7,68 e 7,60. Em sequeiro, a altura de plantas máxima foi 62,91 e 72,85 cm, matéria seca máxima de 40,0 e 44,91 g e o LAI máximo de 6,34 e 6,26. As maiores produtividades agrícola sob irrigação, foram de 6,19 e 5,90 Mg ha-1 nas cultivares AS 3730 e M 8349. Em sequeiro sobressaíram-se as cultivares M 6410 e M 8349 com produtividade de grãos de 3,60 e 3,30 Mg ha-1. Dessa forma, os modelos de crescimento podem ser utilizados para auxiliar a análise de crescimento em função dos dias após a semeadura.(AU)


Assuntos
Glycine max/fisiologia , Estruturas Vegetais/crescimento & desenvolvimento , Brasil , Pesquisa Empírica , Modelos Anatômicos
8.
Rev. bras. ciênc. avic ; 24(4): eRBCA-2021-1578, 2022. graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1415417

Resumo

In recent years, egg production has had an intense growth in Brazil, and Brazilian egg consumption per capita has significantly increased in the last decade. To reduce sanitary and financial risks, decisions regarding the production and health status of the flock must be made based on objective criteria. Our aim was to determine the main "input" variables for the prediction of egg production performance in commercial laying breeder flocks using an ANN model. The software NeuroShellClassifier and NeuroShell Predictor were used to build the ANN. A total of 26 egg-production traits were selected as input variables and eight as output variables. A database of 44,120 Excel cells was generated. For the training and validation of the models, 74.9% and 25.1% of the data were used, respectively. The accuracy of the ANN models was calculated and compared using the analysis of coefficient of multiple determination (R2), mean squared error (MSE), and an assessment of uniform scatter in the residual plots. The models for the outputs "weekly egg production," "weekly incubated egg,", "accumulated commercial egg," and "viability" showed an R2 greater than 0.8. Other models yielded R2 values lower than 0.8. The ANN predicts adequately eight egg-production traits in the breeders of commercial laying hens. The method is an option for data management analysis in the egg industry, providing estimates of the relative contribution of each input variable to the outputs.(AU)


Assuntos
Animais , Galinhas , Redes Neurais de Computação , Ovos/análise , Produtos Avícolas/análise , Simulação por Computador
9.
J. venom. anim. toxins incl. trop. dis ; 28: e20210108, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1386131

Resumo

Background Eugenol shows both antibacterial and antiparasitic activities, suggesting that it might be evaluated as an option for the treatment of praziquantel-resistant schistosome. Methods The in vitro activities of three eugenol derivatives (FB1, FB4 and FB9) on adult worms from Schistosoma mansoni were examined by fluorescence and scanning electron microscopy to analyze effects on the excretory system and integument damage, respectively. Biochemical tests with verapamil (a calcium channel antagonist) and ouabain (a Na+/K+-ATPase pump inhibitor) were used to characterize eugenol derivative interactions with calcium channels and the Na+/K+-ATPase, while in silico analysis identified potential Na+/K+-ATPase binding sites. Results The compounds showed effective doses (ED50) of 0.324 mM (FB1), 0.167 mM (FB4), and 0.340 mM (FB9). In addition, FB4 (0.322 mM), which showed the lowest ED50, ED90 and ED100 (p < 0.05), caused the most damage to the excretory system and integument, according to both fluorescence and scanning electron microscopy analysis. The death of adult worms was delayed by ouabain treatment plus FB1 (192 versus 72 hours) and FB9 (192 versus 168 hours), but the response to FB4 was the same in the presence or absence of ouabain. Besides, no changes were noted when all of the eugenol derivatives were combined with verapamil. Moreover, FB1 and FB9 inhibited Na+/K+-ATPase activity according to in silico analysis but FB4 did not show a time-dependent relationship and may act on targets other than the parasite Na+/K+-ATPase. Conclusion Eugenol derivatives, mainly FB4 when compared to FB1 and FB9, seem to act more effectively on the integument of adult S. mansoni worms.(AU)


Assuntos
Schistosoma/efeitos dos fármacos , Esquistossomose/tratamento farmacológico , Esquistossomicidas/análise , Técnicas In Vitro , Simulação por Computador , Eugenol/análogos & derivados , Doenças Negligenciadas/tratamento farmacológico
10.
Acta sci. vet. (Impr.) ; 50(supl.1): Pub. 813, 2022. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1401423

Resumo

Background: Pelvic fractures are commonly ecountered in cats. The ilium is included in approximately 50% of pelvic fractures in cats. Although conservative management of the pelvic fracture is known to have good prognosis, surgical fixation is recommended for the pelvic fracture with ilial fractures. 3D printing is an accurate digital modeling method by converting two-dimensional (2D) images into 3D model. 3D printing in veterinary medicine has been described in the various orthopedic diseases such angular limb deformities or fractures. The use of 3D model for presurgical planning is helpful to improve the results of complex surgical interventions. The objective of this study is to identify the usefulness of fabricating 3D models based on allogenic 2D data with aid of 3D printer program. Case: A 4-year-old spayed female domestic shorthair cat presented with hindlimb lameness. Radiography revealed left ilial body fracture with multiple fractures including left tuber ischium, pubic symphysis, and bilateral cranial ramuses of pubis. Digital imaging and communication in medicine (DICOM) files of the complete ilium were extracted from a computed tomography (CT) scan of a healthy and castrated male cat of same breed. Volume rendering images were prepared by Slicer program based on DICOM files. After acquired 3D data were converted to STL (Standard Triangulation Language) file for the 3D printing machine, non-fracture involved area was removed except the left ilium using the Meshmixer® software and then data was stored as STL files again. The length of 3D model was adjusted to actual size using 3D printer firmware based on actual size of the ilial length. Subsequently, 3D modelling was performed using 3D printer. The plate was precontoured to conform to the lateral surface of the 3D model. Internal fixation using precontoured plate resulted in accurate bone alignment. The alignment of the ilium remained appropriate throughtout the follow-up period. Complete union was identified 6 months after surgery. Discussion: Although the most common method for the ilial fractures is the application of bone plates to the lateral side of the ilium, bone plate fixation is more challenging in cats owing to the small bone size and small surface area of the fracture sites compared to dogs. Therefore, it is important to make accurate presurgical planning for successful result of a surgery. 3D printing based on actual patient have several limitations including time for complete printing process and additional anesthetic episode to acquire CT images. However, in simple cases, a presurgical CT scan may not be necessary if the plate can be precisely precontured based on the data from the other patient. In this way, the additional financial burden for CT examination also might be reduced. On the other hand, technical difficulty of utilizing hardware and software, and financial availability were another drawback. However, in this current study, most of limitations regarding conventional 3D printing based on actual patient were overcome by the application of the fused deposition modeling (FDM) technology with allogenic data. In the current study, total time for fabrication of 3D model based on FDM technology, was less than 3 h, which are much shorter than the time for conventional 3D printing. The difference of the ilial length between the actual patient and the 3D model was adjusted through the firmware program. Thus, differences of the conformation or size between the 3D model and the ilium of the patient was negligible during the surgery, although 2D images were not acquired from actual patient. Intraoperative contouring of the plate was not required. In conclusion, through presurgical plate contouring by the 3D bone template based on non-patient specific data, successful treatment of the ilial fracture was possible.


Assuntos
Animais , Feminino , Gatos , Ossos Pélvicos/cirurgia , Transplante Homólogo/veterinária , Impressão Tridimensional , Fixação Interna de Fraturas/métodos , Ílio/lesões , Ossos Pélvicos/lesões
11.
Sci. agric ; 78(2): e20190081, 2021. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1497929

Resumo

Multicollinearity is a very common problem in studies that employ path analysis in agronomic crops, which generates unrealistic results and erroneous interpretations. This study was aimed at assessing the path analysis in data obtained from guava tree full-sib based on modelling multiple regressions applying latent variables to neutralize the effects of multicollinearity. Seven explanatory variables were measured – fruit mass (FM), fruit length (FL), fruit diameter (FD), mesocarp thickness (MT), peel thickness (PT), pulp mass (PM), total number of fruits (NTF) –, plus the main dependent variable, total yield per plant (YIELD). In accordance with the multicollinearity scenario, eleven values were tested with the addition of the constant K to the diagonal of the correlation matrix X’X. Path analysis was applied in two models: all the explanatory variables with direct effect on the dependent one and another model with multiple regression with more than one chain and the presence of latent variables. The path analysis in the multivariate methodology of structural equation modelling (SEM), which uses latent variable prediction, provided better results than the traditional and ridge path analyses.


Assuntos
Genótipo , Psidium/genética , Seleção Genética , Correlação de Dados
12.
Sci. agric. ; 78(2): e20190081, 2021. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-27313

Resumo

Multicollinearity is a very common problem in studies that employ path analysis in agronomic crops, which generates unrealistic results and erroneous interpretations. This study was aimed at assessing the path analysis in data obtained from guava tree full-sib based on modelling multiple regressions applying latent variables to neutralize the effects of multicollinearity. Seven explanatory variables were measured fruit mass (FM), fruit length (FL), fruit diameter (FD), mesocarp thickness (MT), peel thickness (PT), pulp mass (PM), total number of fruits (NTF) –, plus the main dependent variable, total yield per plant (YIELD). In accordance with the multicollinearity scenario, eleven values were tested with the addition of the constant K to the diagonal of the correlation matrix XX. Path analysis was applied in two models: all the explanatory variables with direct effect on the dependent one and another model with multiple regression with more than one chain and the presence of latent variables. The path analysis in the multivariate methodology of structural equation modelling (SEM), which uses latent variable prediction, provided better results than the traditional and ridge path analyses.(AU)


Assuntos
Psidium/genética , Seleção Genética , Genótipo , Correlação de Dados
13.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 58(n.esp): e174951, 2021. tab, ilus, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1348268

Resumo

Vehicle-animal collisions represent a serious problem in roadway infrastructure. To avoid these roadway collisions, different mitigation systems have been applied in various regions of the world. In this article, a system for detecting animals on highways is presented using computer vision and machine learning algorithms. The models were trained to classify two groups of animals: capybaras and donkeys. Two variants of the convolutional neural network called Yolo (You only look once) were used, Yolov4 and Yolov4-tiny (a lighter version of the network). The training was carried out using pre-trained models. Detection tests were performed on 147 images. The accuracy results obtained were 84.87% and 79.87% for Yolov4 and Yolov4-tiny, respectively. The proposed system has the potential to improve road safety by reducing or preventing accidents with animals.(AU)


As colisões entre veículos e animais representam um sério problema na infraestrutura rodoviária. Para evitar tais acidentes, medidas mitigatórias têm sido aplicadas em diferentes regiões do mundo. Neste projeto é apresentado um sistema de detecção de animais em rodovias utilizando visão computacional e algoritmo de aprendizado de máquina. Os modelos foram treinados para classificar dois grupos de animais: capivaras e equídeos. Foram utilizadas duas variantes da rede neural convolucional chamada Yolo (você só vê uma vez) ­ Yolov4 e Yolov4-tiny (versão mais leve da rede) ­ e o treinamento foi realizado a partir de modelos pré-treinados. Testes de detecção foram realizados em 147 imagens e os resultados de precisão obtidos foram de 84,87% e 79,87% para Yolov4 e Yolov4-tiny, respectivamente. O sistema proposto tem o potencial de melhorar a segurança rodoviária reduzindo ou prevenindo acidentes com animais.(AU)


Assuntos
Animais , Simulação por Computador , Acidentes de Trânsito , Animais
14.
Braz. j. vet. res. anim. sci ; 58(n.esp): e174951, 2021. tab, ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-764845

Resumo

Vehicle-animal collisions represent a serious problem in roadway infrastructure. To avoid these roadway collisions, different mitigation systems have been applied in various regions of the world. In this article, a system for detecting animals on highways is presented using computer vision and machine learning algorithms. The models were trained to classify two groups of animals: capybaras and donkeys. Two variants of the convolutional neural network called Yolo (You only look once) were used, Yolov4 and Yolov4-tiny (a lighter version of the network). The training was carried out using pre-trained models. Detection tests were performed on 147 images. The accuracy results obtained were 84.87% and 79.87% for Yolov4 and Yolov4-tiny, respectively. The proposed system has the potential to improve road safety by reducing or preventing accidents with animals.(AU)


As colisões entre veículos e animais representam um sério problema na infraestrutura rodoviária. Para evitar tais acidentes, medidas mitigatórias têm sido aplicadas em diferentes regiões do mundo. Neste projeto é apresentado um sistema de detecção de animais em rodovias utilizando visão computacional e algoritmo de aprendizado de máquina. Os modelos foram treinados para classificar dois grupos de animais: capivaras e equídeos. Foram utilizadas duas variantes da rede neural convolucional chamada Yolo (você só vê uma vez) ­ Yolov4 e Yolov4-tiny (versão mais leve da rede) ­ e o treinamento foi realizado a partir de modelos pré-treinados. Testes de detecção foram realizados em 147 imagens e os resultados de precisão obtidos foram de 84,87% e 79,87% para Yolov4 e Yolov4-tiny, respectivamente. O sistema proposto tem o potencial de melhorar a segurança rodoviária reduzindo ou prevenindo acidentes com animais.(AU)


Assuntos
Animais , Simulação por Computador , Acidentes de Trânsito , Animais
15.
Acta cir. bras ; 36(5): e360508, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278108

Resumo

ABSTRACT Purpose To develop and validate a chest cavity simulator for teaching video-assited thoracic surgery (VATS). Methods The first phase of the study consisted of developing a chest cavity simulator. A quasi-experimental study was performed in the second phase, and 25 surgeons and residents participated in a three-stage pulmonary suture experiment. The videos were recorded and timed. Generalized linear regression models for repeated measures were used to analyze the outcome change over time. Results The chest cavity simulator consists of a console simulating the left hemithorax. Among the participants, 96% rated the design, visual aspect, positioning ergonomics, and triangulation of the portals as very good or excellent (face validity). There was a decrease in suturing time in step 1 from 435.7 ± 105 to 355.6 ± 76.8 seconds compared to step 3 (p = 0.001). The evaluation of the simulation effectiveness and performance (content validity) was rated as very good or excellent by 96% ofparticipants. The most experienced surgeon showed significant reduction in procedure time (p = 0.021) (construct validity). Conclusions The thoracic cavity simulator is realistic, showing content and construct validity, and can be used in VATS training. The simulation model allowed skill gain in the endoscopic suture.


Assuntos
Cirurgia Torácica , Treinamento por Simulação , Simulação por Computador , Brasil , Reprodutibilidade dos Testes , Competência Clínica , Endoscopia
16.
J. venom. anim. toxins incl. trop. dis ; 27: e20200073, 2021. tab, graf, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1154769

Resumo

he resistance against antimalarial drugs represents a global challenge in the fight and control of malaria. The Brazilian biodiversity can be an important tool for research and development of new medicinal products. In this context, toxinology is a multidisciplinary approach on the development of new drugs, including the isolation, purification, and evaluation of the pharmacological activities of natural toxins. The present study aimed to evaluate the cytotoxicity, as well as the antimalarial activity in silico and in vitro of four compounds isolated from Rhinella marina venom as potential oral drug prototypes. Methods: Four compounds were challenged against 35 target proteins from P. falciparum and screened to evaluate their physicochemical properties using docking assay in Brazilian Malaria Molecular Targets (BraMMT) software and in silico assay in OCTOPUS® software. The in vitro antimalarial activity of the compounds against the 3D7 Plasmodium falciparum clones were assessed using the SYBR Green I based assay (IC50). For the cytotoxic tests, the LD50 was determined in human pulmonary fibroblast cell line using the [3(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay. Results: All compounds presented a ligand-receptor interaction with ten Plasmodium falciparum-related protein targets, as well as antimalarial activity against chloroquine resistant strain (IC50 = 3.44 µM to 19.11 µM). Three of them (dehydrobufotenine, marinobufagin, and bufalin) showed adequate conditions for oral drug prototypes, with satisfactory prediction of absorption, permeability, and absence of toxicity. In the cell viability assay, only dehydrobufotenin was selective for the parasite. Conclusions: Dehydrobufotenin revealed to be a potential oral drug prototype presenting adequate antimalarial activity and absence of cytotoxicity, therefore should be subjected to further studies.(AU)


Assuntos
Bufanolídeos/administração & dosagem , Bufonidae , Biodiversidade , Malária/imunologia , Antimaláricos , Técnicas In Vitro , Simulação por Computador
17.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 27: e20200073, 2021. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-31982

Resumo

he resistance against antimalarial drugs represents a global challenge in the fight and control of malaria. The Brazilian biodiversity can be an important tool for research and development of new medicinal products. In this context, toxinology is a multidisciplinary approach on the development of new drugs, including the isolation, purification, and evaluation of the pharmacological activities of natural toxins. The present study aimed to evaluate the cytotoxicity, as well as the antimalarial activity in silico and in vitro of four compounds isolated from Rhinella marina venom as potential oral drug prototypes. Methods: Four compounds were challenged against 35 target proteins from P. falciparum and screened to evaluate their physicochemical properties using docking assay in Brazilian Malaria Molecular Targets (BraMMT) software and in silico assay in OCTOPUS® software. The in vitro antimalarial activity of the compounds against the 3D7 Plasmodium falciparum clones were assessed using the SYBR Green I based assay (IC50). For the cytotoxic tests, the LD50 was determined in human pulmonary fibroblast cell line using the [3(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay. Results: All compounds presented a ligand-receptor interaction with ten Plasmodium falciparum-related protein targets, as well as antimalarial activity against chloroquine resistant strain (IC50 = 3.44 µM to 19.11 µM). Three of them (dehydrobufotenine, marinobufagin, and bufalin) showed adequate conditions for oral drug prototypes, with satisfactory prediction of absorption, permeability, and absence of toxicity. In the cell viability assay, only dehydrobufotenin was selective for the parasite. Conclusions: Dehydrobufotenin revealed to be a potential oral drug prototype presenting adequate antimalarial activity and absence of cytotoxicity, therefore should be subjected to further studies.(AU)


Assuntos
Bufanolídeos/administração & dosagem , Bufonidae , Biodiversidade , Malária/imunologia , Antimaláricos , Técnicas In Vitro , Simulação por Computador
18.
Sci. agric ; 77(3): e20180096, 2020. ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1497857

Resumo

Studies that have investigated soil carbon dynamics under Mediterranean conditions are scarce and fragmented and contrasting results have often been reported. This study aimed to fill some gaps in our knowledge by: (i) determining annual dynamics of total (RS) and heterotrophic (RH) soil respiration; (ii) estimating annual cumulative RS and RH; and (iii) investigating the relationships between RS and RH and soil temperature and water content. The study was carried out in central Italy, for a plain and a hilly site, with the focus on two main cropping systems: an alfalfa-based forage system and a wheat-based rotation system. RS and RH showed different dynamics, with spatial and temporal variability across these sites. Estimated annual cumulative RS fluxes were 8.97 and 7.43 t C ha–1 yr–1 for the plain and hilly alfalfa-based sites, respectively, and 4.67 and 5.22 t C ha–1 yr–1 for the plain and hilly wheat-based sites, respectively. The RH components of RS were 4.26 and 3.52 t C ha–1 yr–1 for the plain and hilly alfalfa-based sites, respectively, and 3.89 and 2.45 t C ha–1 yr–1 for the plain and hilly wheat-based sites, respectively. A model with a combination of soil temperature and soil water content explained 43 % to 49 % and 33 % to 67 % of the annual variation of RS and RH, respectively. These findings help to extend our knowledge of Mediterranean cropping systems, although further studies are needed to clarify the effects of management practices on the modelling of soil respiration efflux.


Assuntos
Agricultura Sustentável , Análise do Solo , Medicago sativa , Triticum
19.
Sci. agric. ; 77(3): e20180096, 2020. ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: vti-24942

Resumo

Studies that have investigated soil carbon dynamics under Mediterranean conditions are scarce and fragmented and contrasting results have often been reported. This study aimed to fill some gaps in our knowledge by: (i) determining annual dynamics of total (RS) and heterotrophic (RH) soil respiration; (ii) estimating annual cumulative RS and RH; and (iii) investigating the relationships between RS and RH and soil temperature and water content. The study was carried out in central Italy, for a plain and a hilly site, with the focus on two main cropping systems: an alfalfa-based forage system and a wheat-based rotation system. RS and RH showed different dynamics, with spatial and temporal variability across these sites. Estimated annual cumulative RS fluxes were 8.97 and 7.43 t C ha–1 yr–1 for the plain and hilly alfalfa-based sites, respectively, and 4.67 and 5.22 t C ha–1 yr–1 for the plain and hilly wheat-based sites, respectively. The RH components of RS were 4.26 and 3.52 t C ha–1 yr–1 for the plain and hilly alfalfa-based sites, respectively, and 3.89 and 2.45 t C ha–1 yr–1 for the plain and hilly wheat-based sites, respectively. A model with a combination of soil temperature and soil water content explained 43 % to 49 % and 33 % to 67 % of the annual variation of RS and RH, respectively. These findings help to extend our knowledge of Mediterranean cropping systems, although further studies are needed to clarify the effects of management practices on the modelling of soil respiration efflux.(AU)


Assuntos
Análise do Solo , Medicago sativa , Triticum , Agricultura Sustentável
20.
Semina ciênc. agrar ; 41(06,supl. 2): 3391-3396, 2020. tab
Artigo em Inglês | VETINDEX | ID: biblio-1501691

Resumo

Four mathematical models were used to describe the ruminal disappearance of dry matter (DM) and crude protein (CP) of fish meal and cottonseed meal. Results of DM degradability particularity showed that all the models fitted well (R2 > 0.95), however, considering that values below 0 or above 100 are not biologically justified in ruminal degradability, they are not acceptable. The models I and II were accepted to ruminal DM degradability of fish meal and cottonseed meal data. Only models I and II were successfully fitted to CP degradability of fish meal (R2 > 0.96), and the I, II and III models were acceptable to ruminal CP degradability of cottonseed meal (R2 > 0.98). In terms of effective degradability (ED) of DM and CP, model II generated higher values than other models. To appreciate fully the role of mathematical modelling in the biological sciences, it is necessary to consider the nature of feeds that evaluated and to review the types of models that may be constructed.


Quatro modelos matemáticos foram utilizados para descrever o desaparecimento ruminal da matéria seca (MS) e proteína bruta (PB) da farinha de peixe e farelo de algodão. Os resultados da particularidade da degradabilidade da MS mostraram que todos os modelos se ajustaram bem (R2 > 0,95), no entanto, considerando que valores abaixo de 0 ou acima de 100 não são biologicamente justificados na degradabilidade ruminal, eles não são aceitáveis. Os modelos I e II foram aceitos para a degradabilidade ruminal da MS da farinha de peixe e e o farelo de algodão. Apenas os modelos I e II foram adaptados com sucesso à degradabilidade de PB da farinha de peixe (R2 > 0,96), e os modelos I, II e III foram aceitáveis para a degradabilidade ruminal da PB do farelo de algodão (R2 > 0,98). Em termos de degradabilidade efetiva (DE) da MS e da PB, o modelo II gerou valores mais altos que os demais. Para apreciar plenamente o papel da modelagem matemática nas ciências biológicas, é necessário considerara natureza dos alimentos que foram avaliados e revisar os tipos de modelos que podem ser construídos.


Assuntos
Farinha de Peixe/análise , Ração Animal
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